doc: Change yat2m to allow arbitrary condition names.

* doc/yat2m.c (MAX_CONDITION_NESTING): New.
(gpgone_defined): Remove.
(condition_s, condition_stack, condition_stack_idx): New.
(cond_is_active, cond_in_verbatim): New.
(add_predefined_macro, set_macro, macro_set_p): New.
(evaluate_conditions, push_condition, pop_condition): New.
(parse_file): Rewrite to use the condition stack.
(top_parse_file): Set prefined macros.
(main): Change -D to define arbitrary macros.
--

This change allows the use of other conditionals than "gpgone" and
thus make "gpgtwoone" et al. actually work.  It does now also track
conditionals over included files.

Signed-off-by: Werner Koch <wk@gnupg.org>
scd: pinpad fix for PC/SC on Windows.

* scd/apdu.c (SCARD_CTL_CODE): Fix for Windows.